Today, Neogen and Angus Genetics Inc. announced the availability of a genetic test for DD. Angus breeders can either submit new samples or use archived samples.

“Our experienced and dedicated team is able to provide consistent and rapid service on all of our DNA tests,” said Dr. Stewart Bauck, GeneSeek general manager, in a statement. “Improved DNA technology has allowed us to couple a variety of tests with our GeneSeek Genomic Profiler GGP-HD product as well, in a cost-effective manner.”

“Any animals identified as being homozygous for the mutation shall therefore be considered to be affected by the condition, and are not eligible for registration under Rule 103d,” the statement reads. “In the event that a registered animal is discovered to be affected by the condition, its registration shall be considered null and void, and the Certificate of Registration must be returned to the Association for cancellation.”

Selective breeding and genomics can help reduce or eliminate DD from the cattle population by breeding animals that don’t carry the recessive DD allele.

Genetics crash course

It all starts with alleles, which are different types of the same gene. In many organisms, including mammals such as cattle, each gene is made up of two alleles – one from each parent. A recessive allele only causes a visible trait (known as a phenotype) when the animal has two copies of the same allele (called homozygous). When paired with a dominant allele, the animal is considered heterozygous, meaning it has two different alleles. The animal will display the physical trait coded in the dominant allele. Although heterozygous animals don’t display the recessive trait, they still carry the recessive allele and can pass it along to offspring.